Johns Hopkins University

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY Goal: We will develop and validate a microphysiological platform of human cardiac sympathetic innervation for in vitro modeling of the human cardiac sympathetic innervation and apply autonomic neuron specification and its interaction with a fatal cardiac disease. The heart is heavily innervated by the autonomic nervous system that consists of both parasympathetic and sympathetic nerves, providing feedback control and regulate overall cardiac performance. Historically, the development of new therapeutic agents targeting cardiac neuropathies have utilized animal models, which exhibited various limitations due to the disparity in homeostatic mechanisms of autonomic nervous systems and the inability to recapitulate accurate human disease phenotypes. In our proposed work, we will develop a novel compartmentalized 3D microelectrode array (MEA) co-culture platform to model human sympathetic innervation and address the fundamental questions on sympatho-cardiac connections, reciprocal regulation, and development of cardiac and autonomic cells. Furthermore, with arrhythmogenic cardiomyopathy (ACM) patient-derived human induced pluripotent stem cells (hiPSC), we expect to recapitulate ACM syndromic phenotypes and examine the diseased cardiac sympathetic innervation on our microphysiological platform, conducive to understanding neuromodulation as well as the neuronal contribution to heart function and disease. We will leverage state-of-art techniques developed by our team: (1) high-throughput multimodal 3D microelectrode arrays, (2) single-cell transcriptomes from human autonomic neurons and cardiac cells for a continuum of molecular changes during their interactions, (3) genetic reporter systems with isogenic control cells to define specific human autonomic neuron populations and perform high- resolution analysis of the neuron-cardiac connection, (4) the optogenetic control of neuronal activities on connected cardiac tissue. Focus/Aim: Our proposed research focuses on developing an in vitro platform to study neuro-cardiac interactions with hiPSCs. We will develop and optimize a compartmentalized 3D MEA co- culture platform in multi-well format to monitor electrophysiology properties of cardiomyocytes, sympathetic neurons and neuro-cardiac junction, followed by evaluation of the platform’s ability to support functional synapse formation with optogenetic neuronal stimulation (Aim 1). We will also generate the developmental trajectory of hiPSC-cardiomyocytes connected to hiPSC-sympathetic neurons through single cell transcriptomic analysis, as well as structural and functional changes in hiPSC-CMs following neuronal stimulations (Aim 2). Furthermore, we will examine whether the innervation affects cell fate choice (Aim 2). In Aim 3, we will employ ACM patient- derived hiPSC/hESCs harboring desmosomal gene mutations onto our microphysiological platform and investigate the role of sympathetic innervation in pathogenic phenotypes presented by ACM, which will be validated in vivo. The proposed in vitro model of cardiac autonomic innervation could provide broad applications, including preclinical drug testing and in vitro disease modeling for etiological understanding of cardiac autonomic cardiomyopathies and neuropathies.

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY Today, persons living with HIV (PLWH) face a disproportionate burden of chronic respiratory disease and accelerated lung aging. Despite advances in research that have increased our understanding of lung disease among PLWH, there are significant gaps in our knowledge of factors that impact lung health in this at-risk population. Worldwide ambient air pollution remains a significant, but modifiable, contributor to chronic respiratory morbidity and disease development. While translational studies suggest that HIV increases susceptibility to cigarette smoke, whether this applies to long-term ambient air pollution exposure has not been studied. To date, the impact of long-term air pollution exposure on lung aging in HIV remains unknown. The Study of HIV Infection in the Etiology of Lung Disease (SHIELD), a prospective cohort of 2600 individuals with or at-risk for HIV in Baltimore, MD, provides an ideal platform to efficiently answer questions about the impact of the environment on lung aging for PLWH. Building on the existing SHIELD cohort, we aim to determine if long-term ambient air pollution is a driver of accelerated lung aging in a high-risk population, and if PLWH are more susceptible to the respiratory health effects of pollutant exposure. The proposed research will uniquely characterize the interaction between the environment, HIV, and lung aging. We will add refined measures of long-term ambient air pollution with enhanced precision, in-depth CT phenotyping to capture early lung disease, and molecular markers of biologic aging and susceptibility to exposures, while leveraging longitudinal lung function data from a well-defined cohort of PLWH. We propose three aims to study the impact of long-term exposures on multidimensional (physiologic, radiographic, and biologic) lung aging among PLWH. (Aim 1) To determine the association between long-term ambient pollutant exposure and physiologic lung aging (trajectory of lung function decline) and health related quality of life for PLWH and comparable HIV-uninfected participants; (Aim 2) To define the impact of long-term pollutant exposure on CT measures of radiographic lung aging (small airways disease, air trapping, emphysema) among PLWH; (Aim 3) To determine the association between long-term pollutant exposure and accelerated “biologic” aging, measured via the epigenetic clock, a molecular marker of biologic responses and susceptibility to pollutant exposure. In all aims we will examine how HIV and markers of HIV control increase susceptibility to air pollution. This proposal will provide mentored training in the implementation of an environmental cohort study, the complexities of HIV-lung disease research, advanced biostatical methods, novel CT analysis techniques for lung phenotyping, and the application of epigenetic markers to describe biologic responses and susceptibility to exposures. The career development plan includes expert mentorship, formal coursework, and hands-on experience to facilitate Dr. Raju in achieving his career goal of becoming an independent physician scientist with expertise at the intersection of environmental health disparities, HIV, and lung health research.

NIH Research Projects · FY 2025 · 2022-07

The evolving complexity of healthcare delivery and research requires nurse scientists to integrate advanced methods that span biological, behavioral, and environmental domains while harnessing big data and evidence-based practices. In particular, participant-centered research that builds on participant experience and real-world context is a transformative implementation research paradigm by bridging the gap between science and practice through meaningful end-user engagement to promote health for all. This T32 application requests five years of funding to support a structured predoctoral research training program that prepares nurse scientists to lead rigorous, innovative investigations aimed at improving health outcomes and service delivery across the lifespan. The program offers a comprehensive curriculum and mentored research experience grounded in four thematic cores: participant-centered study design, biological and behavioral measurement, data science and analytics, and applied intervention strategies. These methodological areas are critical for developing practical, scalable solutions that enhance care effectiveness and inform public health practice. Our program faculty and mentors, drawn from the Schools of Nursing, Medicine, and Public Health at Johns Hopkins University, bring extensive expertise in interdisciplinary research, measurement science, and translational methods. Their collective experience provides an exceptional foundation for training the next generation of nurse scientists in advanced research methods and applied healthcare innovation. The two-year training program will recruit four nurses at the predoctoral level each year. Training a new generation of interdisciplinary nurse scientists with strong knowledge and skills in collaborative research practices, measurement, and methodological approaches will further advance our ability to address the complex nature of contemporary healthcare.

NIH Research Projects · FY 2025 · 2022-07

Project Summary The myelodysplastic syndromes (MDS) are the most common clonal blood disorders, characterized by dominance of the bone marrow by abnormal stem cells and impairment of blood cell production. Patients with MDS suffer from combinations of anemia, infection, bleeding, and multiorgan failure from progressive disease. Outcomes are poor, and treatments are inadequate. Key to developing new treatments is better understanding of the mutations which create these diseases. Roughly half of MDS patients have mutations in spliceosome genes, and of these, SF3B1 is the most commonly mutated. Mutant SF3B1 is neomorphic, disrupting RNA splicing to create what we refer to as JEMs (splice Junctions Enriched in Mutant-spliceosome cells), though how JEMs produce MDS phenotypes is unknown. SF3B1 mutation is regarded as a favorable prognostic marker in MDS. Yet, there is considerable heterogeneity in the pathologic features and clinical outcomes of SF3B1-mutant MDS that remains unexplained. As this heterogeneity beguiles effective disease management, its causes need to be better understood. The premise of our proposal is that a key to understanding SF3B1-mutant MDS is to study the differences between distinct SF3B1 mutations. This gene is mutated in hotspots affecting multiple amino acids, and our preliminary data show that specific mutations associate with distinct clinical features, RNA splicing patterns, and responses to therapy. We also have data that SF3B1 mutations disrupt metabolism in specific ways that likely affect sideroblastic anemia and metabolic vulnerabilities, and we have developed novel human models of SF3B1-mutant hematopoiesis with which to study these processes. The proposed work combines the expertise of a physician-scientist (Dr. Dalton) who specializes in cell biology, genetics, and human cell modeling of disease with that of a clinical investigator (Dr. DeZern) who specializes in clinical studies of bone marrow failure disorders. Together, we will pursue three aims: 1) Characterize the landscape of private and shared JEMs among hotspot SF3B1 mutations in MDS. We will use RNA-seq of primary MDS samples and isogenic human cell models to map the RNA splicing landscape of different SF3B1 mutations and use this as a ‘way in’ to understanding the pathways they disrupt. 2) Establish the role of distinct SF3B1 mutations in the growth and differentiation of human hematopoietic cells. We will use primary MDS samples and isogenic cells to determine mechanisms of sideroblastic anemia, cell fitness, and metabolic vulnerability in SF3B1-mutant hematopoietic cells. 3) Define the clinicopathologic features of distinct SF3B1 mutations in MDS. Leveraging the high-quality data from the NHLBI National MDS Study, we will determine how distinct hotspot SF3B1 mutations affect pathologic and clinical features of MDS through multivariate analysis. Successful completion of these aims promises to reveal pathophysiologic mechanisms of RNA splicing, redefine disease classification and prognosis, and improve treatment approaches in MDS.

NIH Research Projects · FY 2024 · 2022-07

PROJECT SUMMARY Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of death due to cancer in the United States and will become the 2nd leading cause of cancer-related death by 2030. PDAC is typically diagnosed late in the disease process when therapeutic options are severely limited, resulting in an overall survival time of <12 months post-diagnosis and a 5-year survival rate of <10%. Therefore, new drugs that prevent PDAC primary and metastatic tumor growth are desperately needed. PDAC tumor cells are extremely proliferative and thus have a high requisite demand for membrane lipids. However, the PDAC tumor microenvironment is poorly vascularized, leading to hypoxia and limited nutrient supply. Lipid synthesis is highly oxygen-consumptive, so neoplastic cells in a hypoxic environment are challenged with meeting the demand for lipids. The sterol regulatory element-binding protein (SREBP) transcription factors maintain cellular lipid supply by increasing synthesis and uptake of cholesterol, fatty acids, and triglycerides. SREBPs are activated when lipid supply is low, and SREBP cleavage activating protein (SCAP) is required for pathway activity. Thus, tumors should require SCAP to adapt to nutrient- limiting conditions and supply lipid for membrane construction. To date, the SREBP pathway has been implicated in the growth and progression of several cancers, including colon, prostate, breast, and glioblastoma. However, the role of the SREBPs in PDAC has not been examined. Using multiple human PDAC cell lines and mouse tumor models, we demonstrated that SCAP is required for PDAC tumor development and growth, making SCAP a novel target for therapeutics. Despite the established requirement for the SREBP pathway in multiple cancers, no potent chemical inhibitor exists. To identify new candidate therapeutics, we developed a robust high throughput assay for SCAP inhibitors. Here, we build on our preliminary studies to identify potent SCAP chemical inhibitors for the treatment of pancreas cancer. AIM 1. To identify candidate SCAP inhibitors by high throughput screening. AIM 2. To validate SCAP inhibitors and conduct preliminary SAR studies. The overall goal of these studies is to identify a series of potent, chemically tractable, validated compounds that inhibit SCAP in at least two orthogonal assays with a dose-response over 100-fold concentration range. Traditional approaches to target lipid metabolism in cancer have focused on inhibition of a single enzyme required for cholesterol, isoprenoid or fatty acid synthesis. SREBPs directly regulate more than 30 genes of lipid metabolism. Thus, inhibiting SCAP will coordinately block multiple synthesis and uptake pathways and represents a novel approach to targeting lipid metabolism in cancer.

NIH Research Projects · FY 2026 · 2022-07

PROJECT SUMMARY (See instructions): In receptor signal transduction, a major goal is to understand how a complex network of biochemical interactions at the cell membrane is spatially coordinated to generate specific cellular responses. It is generally thought that this level of complexity is essential for the tight regulation of information processing in cells, as defects in signaling have been linked to numerous diseases. However, the complexity has created a gap between reconstituted systems and living cells, limiting progress toward a mechanistic understanding of signal transduction. This proposal addresses this challenge by developing a total reconstitution approach that substantially advances our ability to reconstruct complex signaling networks, approaching those in cells, while retaining the experimental strengths of an in vitro approach. We propose a hybrid approach, introducing undiluted cell extracts into model membrane systems, to overcome the fundamental limitations of traditional reconstitution methods and reconstitute cellular complexity. This innovation enables the reconstitution of intracellular signaling as an integrated entity rather than isolated compartments, thus clarifying how signals are amplified, sustained, or attenuated at the membrane. The R00 phase has two aims: 1) reconstituting the receptor tyrosine kinase (RTK) pathway and 2) dissecting the spatiotemporal mechanisms in the RTK pathway. Specific emphasis is placed on using the reconstituted system to study the pressing question of how RTK condensates regulate Ras GTPase activation. The findings are expected to contribute to a quantitative model of RTK signaling, establishing a paradigm for studying other signaling pathways. Such efforts are bringing us beyond a descriptive understanding of signal transduction to a mechanistic framework, offering quantitative insights into abnormal signaling in disease and alternative strategies for therapeutics.

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY / ABSTRACT Public health response to infectious disease epidemics requires multidisciplinary, quantitative, and critical skills to address all aspects of control from preparedness to elimination. The proposed training program will provide critical training in modern methods of infectious disease epidemiology within the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health. All trainees in this program will receive rigorous training in three foundational areas: Epidemiologic Study Design and Inference, Ethics, and Translating Infectious Disease Research through an applied practicum. In addition, trainees will focus on one of three areas of methodological specialization (1) Transmission Modeling and Infectious Disease Dynamics, (2) Molecular Epidemiology and Phylogenetics, or (3) Disease Mapping and Burden Estimation. These three areas of specialization were selected because of their importance across all phases of the response to infectious disease threats, from preparedness, through emergence, endemic control and elimination. The core faculty and affiliate faculty participating in this training program bring strong expertise in each of these areas of methodological specialization, as well as deep expertise in a large number of pathogen systems, and lead projects that offer numerous training opportunities in these areas. Emphasis will be placed on integrating and translating epidemiological and scientific results to public health policy and practice. All trainees will be provided with practical experience in translational research and implementation science through practicums and research projects. Hence, trainees will be required devote a research aim to applying advanced methods to policy and practice. Two post-doctoral and 2-3 pre-doctoral trainees will be supported in each year of the program, and will be paired with both methodological area and pathogen specific mentors. By focusing on critical methodological areas, this training program will provide critical skills that will prepare trainees to conduct important and impactful research in all phases of the infectious disease ‘lifecycle’, from emergence to elimination.

NIH Research Projects · FY 2025 · 2022-07

 PROJECT SUMMARY Johns Hopkins University has recently re-established a multi-disciplinary, multi-school education program in Biomedical Informatics and Data Science (BIDS). The program is centrally coordinated and managed by the newly established Section of Biomedical Informatics and Data Science (BIDS) in the Division of General Internal Medicine. Faculty are drawn from the Johns Hopkins School of Medicine, the Bloomberg School of Public Health, the Whiting School of Engineering, the School of Nursing, and the Krieger School of Arts and Sciences. The program is structured around four tracks: Translational Bioinformatics, Clinical Research Informatics, Healthcare/Clinical Informatics, and Public Health Informatics. The program is built on the decades of informatics training tradition fostered by the Welch Medical Library and the Division of Health Sciences Informatics, now consolidated in the new BIDS Section. The new organization has established tight integration with the University and School of Medicine Education leadership, support systems, and infrastructure. We have revamped and extended our core curriculum to balance traditional informatics topics with current data science principles and methods. Specialized curricula have been developed in depth for each academic track of the program. Because of our newly formalized administrative structure, students are now free to take elective courses anywhere in the University with tuition reciprocity. Students also have access to the deep bench of research programs across informatics, computer science, biomedical engineering, and data science throughout the university, anchored by an ever-growing portfolio of BIDS grants and cooperative agreements in the BIDS Section such as the National COVID Cohort Collaborative (N3C). Thus, BIDS students have unprecedented opportunities for applied practica at depth to enrich and reinforce their education, provide a basis for theses, and more importantly achieve experience as collaborators, contributors, and authors. The University and School of Medicine provide state-of-the-art clinical and basic science data-analytics environments, including our Secure Analytic Framework Environment (SAFE) virtual machines, the Precision Medicine Analytics Platform (PMAP), the state HIE population-based EHR analyses platform (on PMAP), and well-curated clinical data warehouses in OMOP, PCORNet, ACT, and TriNetX formats. Training in biomedical ethics and the responsible conduct of research is deeply embedded in all practica involving patient data. Students have opportunity to work with well-established, well-funded research mentors, and to receive instruction from faculty with a deep commitment to education and training. The strengthening of translational science, multidisciplinary teams, and enterprise-class infrastructure and computer support across Johns Hopkins University provides students with opportunities to witness and participate in the new shape of collaborative science into the future.

NIH Research Projects · FY 2026 · 2022-07

Abstract Aging of skeleton becomes more susceptible to develop autoimmune disease such as rheumatoid arthritis (RA). Increased osteoclast activity and bone resorption is partly responsible for deterioration of skeleton during aging. We have shown that aberrant activation of osteoclast formation in the subchondral bone initiates uncoupled remodeling activity to induce degeneration of joints in both RA and osteoarthritis (OA). The elevated osteoclast activity in the subchondral bone is also responsible for the joint pain. However, the signaling mechanism of increased osteoclast fusion and bone resorption is unclear in RA. Interestingly, sialic acid level in serum and sialylation of cellular receptors continuously increase during with implication of skeleton aging and autoimmune disease. We found that sialylation of TLR2 induced binding to Siglec15 to initiate osteoclast fusion for bone loss. Trap+ mononuclear cells with RANKL undergo cell-cell fusion to form Trap+ multinuclear osteoclasts. The mechanism of RANKL-induced osteoclast fusion and maturation are not fully understood. Our preliminary results showed that RANKL induced transcription of α2,3-sialyltransferase ST3Gal1 in preosteoclasts. Noteworthy, the sialylation of TLR2 by ST3Gal1 induces binding to Siglec15, a member of sialic acid-binding lectins of the immunoglobulin superfamily, to promote osteoclast fusion for bone resorption. In parallel, our preliminary results also showed that the binding of sialylated TLR2 to Siglec 15 induced biased Th17 differentiation of CD4+ T cells at onset of RA development. We now know that Th17 T cells are involved in nearly all major autoimmune diseases, including RA, multiple sclerosis (MS), inflammatory bowel disease (IBD) and systemic lupus erythematosus (SLE). It is critical to understand the divergent functions of Th17 cells in homeostatic and disease states. Th17 cells also promote the maturation of B cells for autoimmune antibody generation. Most importantly, our preliminary results showed that soyasaponin Bb, a triterpenoid saponin from soy, effectively inhibited α2,3-sialyltransferases activity in both aged and RA mice. Thus, we hypothesize that sialylation TLR2-induced osteoclast fusion and biased Th17 differentiation of CD4+ T cells during aging accelerates skeleton deterioration susceptible to development of autoimmune disease such as RA. In the proposed study, we will first characterize mechanism of sialylated TLR2-induced osteoclast fusion in Specific Aim 1. We will then investigate the effect of sialylation of TLR2 on T cells at onset of RA. We will finally examine the therapeutic effect of Soyasaponin Bb sialyltransferase inhibitor on RA. Inhibition of TLR2 sialylation by soyasaponin Bb could mitigate age-induced biased differentiation of Th17 and osteoclast fusion.

NIH Research Projects · FY 2024 · 2022-07

Project Abstract Alzheimer’s disease is a disease of neurodegeneration and aging that affects millions of Americans, and is expected to impact millions more without further significant breakthroughs.1 However, much of the etiology and progression of Alzheimer’s is still unclear, especially given the complex interactions of many different molecular, cellular, and environmental cues that are correlated with phenotypic outcomes. An emerging focus in Alzheimer’s study is the role of the cerebrovasculature in the initiation, progression, and exacerbation of symptomatic disease.2-4 Disruption of the blood-brain barrier, which tightly controls any exchange between systemic circulation and brain tissue, has manifested in post-mortem and in vivo studies of late-stage Alzheimer’s disease as microbleeds, dysfunctional glucose transport, and impaired efflux of toxins;5 additional animal studies have indicated that some vascular dysfunction precedes neuronal degeneration in the progression of the disease.6, 7 Thus, to understand the drivers and progression of Alzheimer’s disease in hopes of identifying therapeutic breakpoints, the role of blood-brain barrier dysfunction must be investigated. To do so, we propose using a tissue-engineered model of the blood-brain barrier with high spatiotemporal resolution to assess its dysfunction under three key categories of perturbation associated with Alzheimer’s disease. These perturbations will span cell-intrinsic mutations associated with Alzheimer’s (APP(Swe) and PSEN(M146V)), extrinsic cues of oxidative stress (hydrogen peroxide exposure), and the systemic influence of aged blood components (exposure to aged vs. young human serum). We hypothesize that this combinatorial approach will best recapitulate human BBB phenotype in Alzheimer’s, and allow for modular study of each contributor. These perturbations will be compared transcriptomically, proteomically, and functionally. Transcriptomic changes will be studied through bulk RNA-sequencing and gene set enrichment analysis to highlight similarities to published human datasets, identify hallmark pathways that are impacted by Alzheimer’s cues, and motivate functional assay design for further validation in the tissue-engineered model. Proteomic and functional assessments include changes to barrier function, cell identity, and validation of pathways implicated by transcriptomic analysis. This study will provide a deeper understanding of the role of the blood- brain barrier in Alzheimer’s progression and emphasize candidate targets for future intervention. This project and related research training will be conducted under the guidance of Dr. Peter Searson at Johns Hopkins University and the Institute for Nanobiotechnology. Skills including functional assay design, stem cell differentiation, microfabrication, and RNA-sequencing analysis will be supported by the educational resources available within the institution. Additional goals of the fellowship training period will incorporate professional development for future career success, with an emphasis on communication, mentorship, and leadership skills.

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY This is an application for the NIH K23 Career Development Award. The goal of the proposed project is to provide the candidate with advanced skills needed to become an independent clinician-scientist using data science techniques to examine the role of social determinants of health in diabetic retinopathy. To facilitate this long-term goal, the candidate proposes a comprehensive training plan including: 1) formal coursework and obtaining a Master of Science in Applied Health Sciences Informatics, 2) practical hands-on training overseen by her multidisciplinary mentoring team who span the fields of medicine, public health, and data science, and 3) involvement in seminars and workshops. Specific goals are to: 1) understand concepts in social determinants of health and principles of public health interventions, 2) develop skills in data science research including informatics and biostatistics, and 3) submit an NIH R01 and other non-NIH grants that build on the findings of this project. The research project will facilitate attainment of the career development goals. Lapses in care is a major preventable cause of vision loss among patients with diabetic retinopathy (DR) and disproportionately affects individuals of the lowest socioeconomic status. Social determinants of health (SDoH) play a critical role in health outcomes and underlie these health inequities. Current attempts to systematically address SDoH in DR have been limited by two missing components: accurate prediction of the at-risk population, and identification of the most impactful SDoH. The focus of this research proposal is to address this gap. In Aim 1) we will use an innovative approach of incorporating neighborhood-level SDoH measures, as obtained from the U.S. Census Bureau measured on the block group level, to predict lapses in care. The hypothesis is that patients from neighborhoods characterized by lower socioeconomic status, more housing and food insecurity, and difficulty with healthcare access and affordability are more likely to experience lapses in DR care. In Aim 2) we will construct a novel comprehensive SDoH framework that links socioeconomic status to lapses in DR care through various intermediary SDoH including housing stability, food security, and healthcare (access, affordability, and quality). We will use mediation analysis to identify the intermediary SDoH that most strongly mediates the impact of socioeconomic status on lapses in DR care. The hypothesis is that transportation to access healthcare is this most critical mediator.

NIH Research Projects · FY 2025 · 2022-07

Project Summary Bilateral loss of vestibular sensation is disabling, with affected individuals suffering chronic disequilibrium, increased risk of falls, and inability to maintain stable vision during head movements typical of daily life. Most individuals with mild or moderate loss compensate through rehabilitative strategies enlisting other senses; however, those with severe loss who fail to compensate have no good therapeutic options. For older individuals who are already contending with decreases in vision, proprioception and other systems that normally contribute to maintaining balance, lack of compensatory reserve can make loss of vestibular sensation even more impactful. Fortunately, when the vestibular nerves are anatomically intact, as is true in most such cases, electrical stimuli encoding head rotation can artificially drive nerve activity to partially restore vestibular sensation, much as a cochlear implant partially restores auditory sensation. In the first-in-human early feasibility study designed to test the safety and efficacy of long-term prosthetic vestibular nerve stimulation as a sensory restoration treatment, we performed unilateral vestibular implantation in 8 adults aged 51-66 years old who had been disabled for 2-23 years by bilateral vestibular hypofunction. We found that vestibular implantation and 24 hr/day motion-modulated prosthetic stimulation targeting the three implanted semicircular canals drives directionally-aligned vestibulo-ocular reflexes, improves objective measures of posture and gait, and improves patient-reported dizziness handicap and vestibular-related disability. However, we do not yet know whether this sensory-restoration treatment will work well in older adults, who are thought to have greater difficultly adapting to asymmetry in input from the two vestibular labyrinths. Drawing on an established design, experienced study team and protocol that have already yielded highly impactful results in the existing study of younger subjects, the proposed research will extend this approach to older adults disabled by bilateral vestibular hypofunction. Results are very likely to yield sustained impact, by clarifying the relative risks and benefits of this intervention in older adults and by providing data that can inform decisions by regulators, policy-makers and third-party payers regarding whether older adults disabled by bilateral vestibular loss should have access to vestibular implantation.

NIH Research Projects · FY 2025 · 2022-07

Project Summary Socioeconomic and racial disparities in cancer care and outcomes among older adults have been persisted and even widened in recent years. At the same time, the lack of safe and affordable housing has become a national crisis. Despite the strong potential for housing insecurity to impact cancer inequities, there is a paucity of evidence connecting these two areas. The Housing assistance, Outcomes, MEdicare, and SEER (HOMES) Study is a highly innovative investigation of the association between housing insecurity and cancer inequities. It focuses on the role of federal housing assistance which, through a variety of programs, including Housing Choice Vouchers, public housing, and multifamily housing, limit household spending on rent and utilities. By increasing housing affordability and stability, improving housing quality, changing neighborhood context, and connecting residents with health and social services, federal housing assistance has the potential to improve the quality of care that patients with cancer receive and, more broadly, shed light on the intersection of cancer and housing. The study focuses on older adults diagnosed with breast, colorectal, prostate, and non- small cell lung cancers given their high incidence and well-documented inequities. The study makes use of a novel dataset being constructed by the National Cancer Institute that merges linked SEER-Medicare data on patients diagnosed (2006-2019) with U.S. Department of Housing and Urban Development data on the receipt of federal housing assistance. Because individuals who receive housing assistance may be fundamentally different from those who do not, the study makes use of an innovative pseudo-waitlist control design that leverages the limited supply of housing assistance relative to demand and the random timing of the receipt of housing assistance. The first aim examines the overall relationship between receipt of federal housing assistance and cancer care (time to treatment, receipt of guideline concordant care, emergency department visits) and outcomes (stage at diagnosis). The second aim investigates whether these relationships vary by cancer site and, given experiences of systemic racism that intersect with cancer disparities and housing policy, by race/ethnicity. The final aim studies whether the association between housing assistance and cancer care and outcomes varies by the form of housing assistance and across different neighborhood contexts. Informed by a policy advisory committee in conjunction with representatives from the American Cancer Society Cancer Action Network and National Cancer Roundtables, the HOMES Study has the strong potential to provide actionable housing and cancer policy recommendations and inform changes to practice designed to improve cancer equity.

NIH Research Projects · FY 2024 · 2022-07

PROJECT SUMMARY/ABSTRACT Adult stem cells are crucial for regeneration, tissue repair after injury, and developmental processes such as spermatogenesis. These cells ensure both tissue growth and renewal by dividing asymmetrically, producing one daughter stem cell and one daughter that differentiates 1,2. Stem cells exist in a dynamic microenvironment termed the niche that provides signals to ensure the maintenance and self-renewal of the adult stem cell population1–5. An appreciation of the dynamic communication between stem cells and their niche is vital to understand processes such as reproduction, oncogenesis, aging, development, and regeneration. Much is known about signals sent from niche cells and received by stem cells3,6–13; however, little is known about signaling in the opposite direction: from stem cells back to their niche. Here, I use the testis stem cell niche of Drosophila melanogaster to explore signaling from stem cells back to their niche as well as the role of endocytic tumor suppressor genes in this signaling. Endocytosis regulates a myriad of signaling pathways14–18. My preliminary data indicate that knockdown of an endocytic gene in somatic stem cells greatly increases the size of adjacent niche cells and, consequently, the niche itself. Since the way that endocytic genes non-autonomously regulate niche size is unknown, but may apply widely to other niches. In Aim 1, I further characterize this phenotype by assessing the role of endocytosis in mediating signaling within the Drosophila testis stem cell niche. I will specifically knock down genes regulating endocytosis from cyst stem cells and characterize the resultant changes in neighboring niche cells, focusing on niche cell size, morphology, and ploidy. I will also examine the activity of a small set of well-characterized signaling pathways involved in cell growth in wild-type and endocytic mutant testes. I will follow up with genetic loss and gain-of- funditon analysis for pathways with changes such as the JAK-STAT pathway (preliminary data). In Aim 2, I more broadly investigate signaling from other cells to the niche cells by performing a screen of candidate niche cell signaling pathway receptors identified in our recent single-cell transcriptomic datasets. This will greatly expand our understanding of the signaling pathways requred for niche cell fate, function, size and/or quiescence. Overall, these proposed experiments will further illuminate cell signaling dynamics within the Drosophila testis stem cell niche, with implications for niches in other tissues and organisms. I will conduct this work in the lab of Dr. Erika Matunis at the Johns Hopkins School of Medicine, where I have access to over 50 departmental and core facilities and resources including Drosophila media, flow cytometry, microscopy, genetics and genomics, and a supportive mentoring team. I will supplement my research training by strengthening my quantitative skills through workshops and courses, and my communication skills through grant and manuscript writing and presentations at conferences. Furthermore, I will gain teaching experience by serving as a teaching assistant and mentoring undergraduates in the lab.

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY Metabolic and inflammatory disorders such as autoimmune and neurodegenerative diseases are increasing at alarming rates. Many of these are not tissue-specific occurrences but complex and often overlapping pathologies of unknown origin for which no cure exists. Examples are concurring pathologies of the gut-liver axis, such as inflammatory bowel disease and inflammatory pathologies of the liver. The discovery of “unconventional” T lymphocytes and their ability to respond to non-peptide antigens, marks a new area in the exploration of how migratory cells and immunometabolic networks shape the emergence of autoimmune and metabolic diseases. These are comprised of a heterogeneous group of lymphocytes, such as mucosa-associated invariant T cells, whose invariant TCR can recognize cellular and microbial metabolites via presentation through the MHC-like receptor 1 (MR1). Emerging evidence suggest MR1-restricted T cells to be implicated in a wide variety of disorders ranging from ulcerative colitis to type 1 diabetes, autoimmune hepatitis and multiple sclerosis via TCR-specific and non-specific means. However, lack of models relevant to human physiology represents a significant hurdle in our understanding of how MR1-restricted T cells affect the host and diseases. We have developed an approach that utilizes multiorgan human microphysiological models (MOMPS) of donor-matched tissues and unbiased systems biology tools to gain granular insight into causal relationships between cellular crosstalk and immunometabolic illnesses. In order to gain critical knowledge about the heterogeneity and functionality of MR1-restricted lymphocytes, we will combine single-cell characterization of human MR1-restricted T cells across donor-matched tissues and circulation, with mechanistic studies in a microphysiological model of the gut-liver axis. These MOMPS will be used to systematically search for causal relationships between MR1-restricted lymphocytes, tissues, and external factors by reconstructing donor tissue at various levels of complexity. Each level will be challenged via predetermined inflammatory and metabolic perturbations. Multiomic observation of changes based on interaction and perturbation at each degree of complexity will allow us to construct interaction networks that reveal causal relationships among entities. With computational tools and resolution into molecular underpinnings of cellular and tissue homeostasis, MOMPS represent a unique opportunity to systematically dissect how interactions at a lower order inform new behavior at the macro scale within and between organ systems. While the gut-liver axis will serve as a model in this proposal, the developed approach, together with fundamental biological insights into MR1 expression by parenchymal tissue and function of MR1-restricted T cells, will be applicable to other organ systems and a variety of pathologies. Our overarching goal is to identify tangible targets and new cell-based approaches to modulate autoimmune pathologies but also contribute new tools that shed light on the fundamental origins of complex diseases.

NIH Research Projects · FY 2026 · 2022-06

Obesity continues to rise worldwide. Maternal obesity and consumption of high calorie diets continue to be public health concerns. The intrauterine and early postnatal environment provides support that is critical to the proper development and health of offspring. Maternal high fat (HF) diet consumption during pregnancy can have persistent detrimental effects on the fetus that predispose to obesity and its comorbidities. Our preliminary data in a rat model suggest that maternal HF diet has negative consequences on offspring controls of food intake via the gut- brain axis. Our overarching hypothesis is that gut dysbiosis resulting from perinatal exposure to maternal HF diet alters development of the gut-brain axis and vagally-mediated controls of feeding in offspring leading to increased susceptibility to obesity and other metabolic disorders. Aim 1 will determine how vagally-mediated controls of feeding are altered in rat offspring from dams consuming a HF during pregnancy and lactation. We hypothesize that HF offspring will be less sensitive to peripheral gut hormones, meal pre-loads, and/or nutrients that normally promote satiety. Aim 2 will determine how vagal communication between the gut and the brain is altered in HF offspring. We hypothesize that decreased satiation responses occur because (a) there is an alteration in the structure of VAN projections from the gut to the brain, (b) deficits in enteroendocrine cell number or function, and/or (c) the vagus nerve is less responsive to gut feedback signals. Aim 3 will define the role of gut microbiota composition in HF offspring propensity to obesity and other metabolic disorders. Our preliminary data indicate that HF offspring have gut dysbiosis and greater intestinal permeability by the time that they are weaned at postnatal day 21. Dysbiosis is sufficient to alter vagal structure and function, therefore we hypothesize that gut dysbiosis in HF offspring negatively affects gut-brain axis development and function. We will transfer dysbiotic HF microbiota to germ-free neonates to test sufficiency of dysbiosis in altered gut-brain axis function and determine whether use of prebiotics to normalize microbiota composition of HF fed dams, and consequently their offspring, will improve offspring gut-brain axis development and function. Together the proposed experiments will identify components of the gut-brain axis that are altered by early life exposure to maternal HF diet and could be targets for intervention to prevent adverse long-term metabolic consequences in HF offspring.

NIH Research Projects · FY 2026 · 2022-06

The Johns Hopkins University (JHU) proposes the creation of the Center for Community Health: Addressing Regional Maryland Environmental Determinants of Diseases (CHARMED). The strategic vision of the Center is to serve as the nexus of community- engaged environmental research at JHU and in the Maryland region (Washington DC, Baltimore (referred to as CHARM City) and Pennsylvania extending to the New York State Border) by providing focus, research, and leadership for promotion of transformative environmental health science research that will improve human health. The overarching mission is to understand how exposures to environmental factors cause adverse health outcomes and then to translate these findings into action to protect and promote the health and well-being of communities in the Maryland region. This mission has been informed by and will continue to be guided by strong partnerships between community leaders and CHARMED members (52) drawn from the Johns Hopkins University, and the University of Maryland at College Park. The synergistic combination of basic, population and community-engagement scientists within CHARMED promotes translational research that addresses fundamental questions and translates knowledge into action to have a major impact on human health in the Maryland region, consistent with the NIEHS Strategic Plan. Our mission is accomplished through five aims. Aim 1: Advance translational environmental health research that will improve community health outcomes in the Maryland region as it relates to the thematic foci of the Center. The Thematic Research Groups are: 1) Cardiorespiratory Health and Airborne Contaminants; 2) Chemical Mixtures and Emerging Contaminants, and Health; and 3) Community, Social, and Environmental Determinants of Health. Aim 2. Promote translation of data to knowledge to action by creating and strengthening strategic partnerships with communities and stakeholders to address CHARMED using community-engaged research approaches (Community Engagement Core). Aim 3. Establish and support a facility core structure {Integrated Health Sciences Facility Core (IHSFC), and Exposure Characterization and Modeling Facility Core (ECMC) that enables the mission. The IHSFC will provide assistance with human subject study design, and employ biostatistical, big data, and bioinformatic analyses and integrate “omics” including metabolomics data to predict adverse outcomes. Aim 4. Build capacity in environmental health through a comprehensive strategy that includes fostering (career development, Core Workshops), and supporting (ESI Mentored Scholars Program, pilot funds, access to facility cores) both early stage and senior investigators conducting community environmental health research for the first time. Harnessing the scientific capacity of the Center will facilitate translation of the Center’s finding into evidence-based approaches for environmental exposure mitigation and disease prevention to improve human health in Maryland and beyond.

NIH Research Projects · FY 2025 · 2022-06

SUMMARY Lipids are transferred between membranes by vesicular and non-vesicular routes. Many microorganisms that infect mammalian cells subvert the function of these host cellular lipid trafficking pathways to acquire lipids. Toxoplasma gondii is an obligate intracellular parasite that multiplies in the cytoplasm of mammalian cells within a self-made membrane-bound compartment – the parasitophorous vacuole (PV). The PV of T. gondii does not fuse with host organelles. However, we showed that the parasite’s intracellular survival relies on lipids retrieved from various mammalian organelles. For example, T. gondii scavenges cholesterol and sphingolipids from host endocytic organelles and Golgi vesicles, respectively, which raises the perplexing question of how T. gondii can access the lipid content of these organelles without fusion. To address this issue, our first strategy was to analyze vesicular trafficking pathways in infected mammalian cells. We showed that Toxoplasma intercepts mammalian Rab vesicles associated with recycling, endocytic and secretory pathways, and sequesters these vesicles into a network of membranous tubules appended to the PV membrane. Our second approach was to analyze non- vesicular routes of lipid transfer, specifically Membrane Contact Sites (MCS). By examining the physical connectivity of mammalian host organelles with the PV membrane, we showed that Toxoplasma attracts host ER tubules and lipid droplets to the PV, where they are closely apposed to the PV membrane at distances reminiscent of inter-organelle contacts. Mammalian ER-resident Vesicle-Associated Membrane Proteins (VAP), components of MCS, are associated with the PV membrane, suggesting the potential exploitation of Lipid Transfer Proteins by Toxoplasma for lipid acquisition. Based on these preliminary observations, we propose two models for lipid scavenging by Toxoplasma either mammalian vesicular or non-vesicular lipid transport pathways. We will assess the steps of these models by defining the molecular machineries and mechanisms involved in the interception of host vesicular pathways by T. gondii (Aim 1), the formation of a network of membranous tubules in the PV and its role in mammalian organelle sequestration (Aim 2) and the acquisition of lipids via non-vesicular transfer from mammalian organelles closely associated with the PVM, possibly through MCS (Aim 3). Completing these aims would unravel the complexity of lipid salvage processes mediated by Toxoplasma, providing mechanistic details and identifying future targets for intervention. Indeed, T. gondii can cause fatal encephalitis in immunocompromised individuals, and current treatment options for toxoplasmosis are limited. Furthermore, studying the mechanisms used by Toxoplasma to usurp Rab-mediated vesicle trafficking may yield valuable insights into how Rab GTPases coordinate membrane transport in mammalian cells. Examining the potential strategies developed by Toxoplasma to exploit MCS may also provide important information on how the loss of MCS affect mammalian cellular physiology and organismal function.

NIH Research Projects · FY 2025 · 2022-06

PROJECT SUMMARY As the number of adults age 65 and older continue to increase, the prevalence of Alzheimer’s disease and other related dementias (ADRD) is also expected to increase in the U.S. Neuropsychiatric symptoms (NPS) such as agitation, apathy, depression, and sleep disturbance are highly prevalent in patients with ADRD, with up to 97% of the individuals suffering at least one NPS over the disease course. NPS requires considerable management and time by care partners, and are associated with rapid cognitive and functional decline, worse quality of life, greater care partner burden, and earlier nursing home admissions. Although nonpharmacological intervention for NPS is recommended, psychotropic medications continue to be widely prescribed, resulting in adverse events. Similar to ADRD, the prevalence of hearing loss increases with age. However, hearing care as tertiary prevention for older adults who have already developed cognitive impairment has largely been ignored. MPIs and the Co-Is of the current proposal have been working together for many years, demonstrating that i) there is a high prevalence of hearing loss among indiviudals with mild cognitive impairment (MCI) and ADRD, ii) increasing severity of hearing loss is associated with greater number of NPS and NPS severity, and that iii) a user-centered hearing care intervention that utilizes emerging over-the-counter (OTC) hearing technology may ameliorate NPS. The current proposal is based upon a prior NIA Stage 1b trial that involved an initial pilot study of a hearing care intervention that utilized OTC hearing devices and was delivered in an outpatient setting. The proposed study returns to Stage 1a and 1b to refine and test the preliminary efficacy of a revised hearing care intervention strategy that targets NPS and examines the underlying mechanism(s) of action. Aim 1 seeks to refine the hearing care intervention through a Stage 1a study that involves consultation with experts and end-users to develop a revised intervention protocol that integrates the latest evidence-informed approaches to NPS along with alignment with theoretical frameworks, consideration of implementation challenges encountered in the initial pilot study, and the ability to deliver the intervention in various settings, including the home. Aim 2 will then assess the preliminary efficacy of the revised hearing care intervention through a larger Stage 1b randomized controlled trial, which will allow for greater rigor in assessing the intervention than prior work. Aim 3 will employ a mixed methods approach to characterize response heterogeneity and underlying mechanism(s) of action. The proposed study embraces the iterative and multidirectional nature of the NIA Stage Model with the goal of developing impactful behavioral interventions that reach the maximum level of potency and potentially implementable to the maximum number of older adults. This proposal builds critical foundational knowledge regarding the role of hearing care as an integral component of managing NPS. These findings will directly translate to a larger Stage 2/3 efficacy trial.

NIH Research Projects · FY 2025 · 2022-06

Project Summary. Despite the efficacious application of immune checkpoint therapy (ICT) across a broad range of cancers, only a subset of patients experience remarkable clinical responses and survival. The challenge facing clinicians and researchers alike is how to deliver the most effective and timely immunotherapy to patients. From clinical trial data it is becoming increasingly evident that a single biomarker is unlikely to capture the scope and breadth of clinical responses to ICT. Rather, incorporation of multiple biomarker panels, including both pharmacodynamic and predictive biomarkers, has become a necessity. However, the number of tests that can be performed with baseline and on-treatment biopsies is limited by the amount of biopsy tissue, and has several shortcomings including inter- and intra-tumoral heterogeneity and sampling errors. Those problems are compounded in patients with metastatic disease and difficult-to-access locations. Imaging methods such as positron emission tomography (PET) enable repetitive evaluation of the whole body and facilitate real-time quantification of pharmacodynamic effects. Also, in recent years on-demand kit formulations of radiopharmaceutical preparations have enabled widespread and routine clinical use of PET in cancer care. However, PET is underutilized in guiding ICT due to the limited access to molecularly targeted radiotracers that accurately report on the activity of the immune infiltrate. Generator-produced Gallium-68-labeled radiopharmaceuticals, in kit formulation or otherwise, are increasingly used in the US and across the globe as theranostic tools for cancer but have not been reported with a focus on advancing ICT. Our project addresses the need for non-invasive biomarkers for guiding ICT with an objective to develop, translate and disseminate a radiopharmaceutical for measuring programmed death ligand 1 (PDL1). We will develop a peptide-based Gallium-68-labeled radiopharmaceutical for measuring PDL1 levels to guide ICT and conduct a first-in-human study in cancer patients. Moreover, we will create a single vial kit formulation of that agent to enable convenient radiopharmaceutical preparation and dissemination. Our radiotracer is peptide-derived and uniquely capable of measuring pharmacodynamic effects of any PD(L)-1 therapeutic in situ in 60 min. We expect that the proposed approach will be a valuable addition to ICT, especially as a non-invasive biomarker. The results generated will enable a fundamental advance in clinical management of patients undergoing ICT and carried out in close partnership with industry with an eye towards dissemination and broad access.

NIH Research Projects · FY 2025 · 2022-06

Project Summary/Abstract The use of combination antiretroviral therapy (cART) has significantly reduced HIV-related morbidity and mortality. However, cART may exacerbate the central nervous system (CNS)-related adverse effects on mental health for people with HIV (PWH). These adverse effects may result in ART discontinuation with undesirable downstream consequences such as HIV disease progression, decreased health outcomes, and increased likelihood of HIV transmission, causing public health concerns. Depression is the most frequently reported mental health comorbidity caused by CNS injury in PWH, with prevalence ranging from 20% to 60%. Understanding factors (e.g., drug-drug interactions) contributing to ART-related depression is critical and remains a high priority NIMH research area. In addition, since PWH must continue cART indefinitely, optimizing sequential cART treatments over a long-time span tailored to individuals’ evolving clinical characteristics and treatment histories is important for improving long-term mental health for PWH. However, there are numerous possible drug combinations with complicated drug-drug interactions and thus creating complex data patterns, such as heterogeneity, high-dimensionality, and sparseness, making it highly challenging to develop appropriate statistical models for these problems - which is a critical gap we aim to fill. This proposal will leverage large public HIV datasets, including Women's Interagency HIV Study (WIHS), to develop data-driven approaches to facilitate deciphering cART-depression relations and guide more effective cART treatments. This proposal is organized into three aims: 1) Develop Bayesian methods to learn longitudinal cART effects on depression and investigate effect modifiers (e.g., polymorphic drug metabolism, aging); 2) Develop Bayesian decision frameworks to optimize personalized sequential cART assignments with the goal of improving long-term mental health outcomes for PWH; (3) encapsulate statistical methods and computational algorithms into user-friendly open-source software for practical use, clinical translation, and dissemination. Findings from this study are expected to expand our understanding of cART effects on depression, and have potential clinical utility to facilitate precision medicine in HIV.

NIH Research Projects · FY 2025 · 2022-06

ABSTRACT The Coronavirus Disease 2019 (COVID-19) pandemic has had an unprecedented impact on the lives of people worldwide. Yet, the effect on persons living with HIV (PLWH) is not known. Emerging evidence suggests that PLWH have a similar or modestly higher risk of COVID-19 acquisition, and higher risk for worse COVID-19 outcomes, including hospitalization and death. However, the data has been mixed as several studies have suggested no difference in clinical outcomes. Several studies also found that outcomes are worse among those without viral suppression and those with lower CD4 counts, highlighting the importance of continued HIV care. Yet, early reports suggest that COVID-19 has disrupted services across the HIV care continuum. As the pandemic continues to unfold, it is critical to better characterize the relationship between COVID and outcomes among PLWH. In addition, we need to identify how the pandemic and the public health strategies to combat the pandemic impacted the provision of care for PLWH, as well as whether any adverse effects are lasting. Approximately 40% of PLWH are enrolled in Medicaid. The proposed project will include Medicaid beneficiaries from 27 states and Washington, DC between 2018 and 2024 with a conservative estimate of 25 million beneficiaries and 275,000 PLWH enrolled annually. Medicaid is an important complement to HIV cohort studies as it affords us the breadth of data to evaluate differences by geographic location, social determinants of health at the community level, as well as among important sub-populations. We will assess the relationship between HIV and COVID-19 disease, including on hospitalization due to COVID-19 and adverse conditions due to COVID like post-acute sequala of COVID-19 (PASC). We will also evaluate the impact of the COVID19 pandemic on the provision of care for prevention of HIV and HIV care. We will assess care across the HIV care continuum including PrEP prescription, HIV testing, and annual HIV care visits, viral load tests, and ARV medication possession ratio. We will also evaluate impacts on the provision of care for non-HIV conditions, including annual wellness visits, preventive screenings and health condition management. We will compare care rates during the pre-COVID period (2001-2019), acute COVID period (2020-2021), and post-acute COVID period (2022-2024) overall and by geographic location (state, urban/rural, local government area [LGA], smallest government region e.g. county, city, town, etc.) and regional severity of COVID-19 cases and COVID- 19 policies. Findings from the proposed study will help inform and target interventions to improve care for PLWH in the future.

NIH Research Projects · FY 2026 · 2022-06

Very preterm infants are prone to numerous medical complications with lifelong impact. Amongst the most serious are severe intraventricular hemorrhage (sIVH) and the subsequent progression to posthemorrhagic hydrocephalus (PHH). Currently, the only treatment for PHH is surgery, most commonly with shunts that are prone to malfunction across the lifespan. Children with sIVH and PHH are also at high risk for intellectual disability, behavioral problems, neurosensory impairment, cerebral palsy and epilepsy. Emerging evidence suggests that the cellular and molecular events regulating cerebrospinal fluid (CSF) dynamics, including CSF secretion, propulsion and reabsorption, develop during the third trimester and the first few months postnatally. Maturation of these highly subspecialized and metabolically active cellular processes spatially and temporally overlaps with preterm birth and IVH, and are thus vulnerable to injury over an extended period. Most importantly, these processes are responsive to neurorestorative interventions with re-purposed medications, raising the possibility of using medical treatment after sIVH to prevent progression to PHH and the need for shunts. Preclinical data show that melatonin (MLT) and erythropoietin (EPO), when administered in a sustained dosing regimen, can prevent the hallmarks of progression from early postnatal sIVH to subsequent PHH, including macrocephaly and ventriculomegaly. Combination therapy is required as neither agent alone prevents PHH. In human preterm infants, MLT and EPO have been safely used as monotherapy in clinical trials with similar dosing regimens. We propose a Phase I, single institution, randomized, double-blind trial for very preterm infants with sIVH to define a safe combination dose of MLT and EPO. With IRB, IND and primary neonatologist approval, and informed consent, a maximum of 60 very preterm neonates with sIVH will be enrolled, treated through 33w6/7d, and followed to 37w6/7d. Neonates will be randomized 3:1 between MLT+EPO and placebo, with all receiving standard of care. Concurrent controls are needed due to fluctuations in preterm birth co-morbidities and mortality. Masking is essential to reduce attribution bias. The primary endpoint is a composite serious adverse event (SAE)/dose limiting toxicity (DLT) including death, potential MLT-realted DLT: severe liver function abnormalities compared to age-matched peers with sIVH, and known EPO-related SAE: thrombosis, polycythemia, and hypertension. No MLT-related SAE have emerged in clinical trials thus far. We hypothesize that the MLT+EPO SAE/DLT rate will not be higher than the placebo rate. Secondary outcomes will be rate of co-morbidities of preterm birth. Exploratory data, collected to guide design of future clinical trials for efficacy, will include serial neuro-imaging metrics acquired from clinical images, serial neonatal neurodevelopmental examinations, serum and urine MLT and EPO levels, and liquid biomarkers. Successful implementation of this initial safety trial will provide essential data to guide the next stage of clinical trials to test if sustained MLT+EPO treatment can reduce the need for surgical intervention, and avoid the lifelong burden of shunted hydrocephalus.

NIH Research Projects · FY 2025 · 2022-06

Congenital heart defects (CHD) are the leading cause of birth defect-associated illness and death. Neurodevelopmental delays and disabilities are the most frequent and significant consequence for CHD survivors. Efforts to reduce morbidity and improve outcomes have primarily focused on surgical techniques, cardiopulmonary bypass (CPB) strategies and pharmacologic therapies without much success. Exposure to industrial chemicals in the health care environment are increasingly being recognized as harmful, and maybe a mechanism for these poor outcomes in CHD. Cyclohexanone, is a hazardous organic industrial solvent used principally in health care as a joining compound in the fabrication of plastic medical devices. Cyclohexanone has been shown to leach from IV infusion sets and the CPB circuit and in animal studies, with significant cardiovascular effects. Therefore, our hypothesis is that cyclohexanone derived from medical plastics is associated with adverse cardiovascular and neurodevelopmental outcomes in congenital cardiac surgery. We now have significant and compelling pilot data in neonates undergoing cardiac surgery that there is a) substantial cyclohexanone exposure from IV infusions and CPB and b) with adjusted analysis, cyclohexanone levels were significantly associated with adverse post-operative cardiovascular outcomes, and worse 12 month neurodevelopmental outcomes, thus supporting our hypothesis. Our long-term goal is to develop new prevention strategies and more precise treatments to improve outcomes for neonates undergoing surgery with CPB. We will approach this hypothesis using samples and outcomes from the discovery cohort: the completed NHLBI multicenter Trial NCT01579513, entitled “Corticosteroid Therapy in Neonates Undergoing Cardiopulmonary Bypass (MP trial)”, Eric Graham, PI (n=190, randomized to MP (methylprednisolone) therapy or placebo) and the completed external validation cohort the University of Toronto, “Clinical Assessment of Thrombosis in Children After Heart Surgery: The CATCH Study” (NCT01435473), Brian McCrindle and Cedric Manlhiot (PIs) (N=327, <5 years old) and a neonatal cardiac surgery from the University of Michigan (N=59), Mark Russell, PI. With the following Specific Aims we propose to: Aim 1) Determine if serum perioperative cyclohexanone levels are associated with perioperative morbidity, mortality, and neurodevelopmental outcomes. Aim 2) Determine cyclohexanone exposure sources and removal using zeolite molecular sieves. Finally, Aim 3) Determine cyclohexanone neural toxicity, blood brain barrier and learning/memory effects. These Aims describe a paradigm shift in the mechanism of reduced neonatal heart surgery outcomes. Innovation includes discovery of the novel role of the industrial organic solvent contaminant cyclohexanone from medical plastic fabrication on neonatal cardiac surgery clinical outcomes and methods for removal. Reduction of organic solvent exposure from medical plastics offers an immediate and actionable means to improve neonatal cardiac surgical outcomes.

NIH Research Projects · FY 2026 · 2022-06

Among couples trying to conceive, 10-15% will be affected by infertility, which can be caused by impaired gametogenesis. Effective post-transcriptional gene regulation by RNA-binding proteins (RBPs) is crucial for normal gametogenesis, with mutations in RBPs impairing such regulation and causing infertility in humans. For example, the Deleted in Azoospermia (DAZ) family of RBPs are essential for human fertility, because during spermatogenesis they regulate translation of a subset of mRNAs by binding to their 3′ UTRs; their molecular mechanism of action was understood only after their Drosophila ortholog was identified and studied genetically. However, the full repertoire of RBPs that are essential for gametogenesis is currently unknown. To fully understand the complex post-transcriptional gene regulation during gametogenesis, it is critical to identify novel RBPs that are important for these processes and elucidate their molecular functions and mechanisms of action. We have recently identified three previously uncharacterized RBPs (MARF1, Tanenashi, and CG44249) that are essential for fertility in Drosophila. Our data suggest that MARF1, which is expressed in oocytes and is required for female fertility, regulates mRNA poly-A tail length during oogenesis. Tanenashi, which is expressed in spermatocytes and is required for male fertility, plays roles in promoting the expression and splicing of male fertility factor genes containing mega-base-sized introns with highly repetitive DNA sequence on the Y chromosome during spermatogenesis. CG44249, which is expressed in ovaries and is required for female fertility, likely plays a role in splicing regulation during oogenesis. We also showed that a fourth RBP (Loqs-PB), which is important for female fertility and germline stem cell maintenance in ovaries, regulates the length of microRNAs in ovaries. These four RBPs are conserved from flies to humans. Using Drosophila, I now propose to further investigate these four RBPs, and determine their precise molecular functions and mechanisms of action in gametogenesis. By investigating mutant flies in vivo and the proteins in vitro, we will test our hypothesis that: (i) these RBPs each bind specific target RNAs by recognizing specific RNA sequence and/or structure motifs, and (ii) thereby promote or inhibit the processing of bound RNAs at specific molecular steps, allowing highly regulated spatiotemporal expression of targeted genes during gametogenesis. These studies will advance our fundamental knowledge of the molecular mechanisms of post- transcriptional regulation of gene expression, especially by regulating the mRNA poly-A tail length, mRNA splicing, and microRNA length, during gametogenesis, providing potential for improved diagnosis and treatment of human infertility.